1. Field of the Invention
The present invention relates to a touch-screen stylus pen, and more particularly to a pen head configuration structure for a capacitive touch-screen stylus pen.
2. Description of the Prior Art
A capacitive touch-screen comprises a glass screen, a transparent film layer on the glass screen, a conductive layer, and a piece of glass to protect the conductive layer. The design of dual-glass is to protect the conductive layer and a sensor. The principle of the capacitive touch-screen is that when the user's finger touches a metallic layer, the electric field of the human body and the touchscreen will form a coupling capacitance. For high-frequency current, capacitance is a direct conductor. The finger will draw less current from the contact. The current will flow out from the electrodes of the four corners of the touchscreen. The current passing the four electrodes is proportional to the distance from the finger to the four corners. A controller gets the position of the contact by calculating the four current proportions.
There is sweat or other dirty objects on the finger to dirty the touchscreen when writing and to influence the visual effect. Thus, a capacitive touch-screen stylus pen is developed. The capacitive touch-screen stylus pen comprises a conductive pen head and a pen body to transmit the induced current of the human body. As known by the definition of the plate capacitor, the capacitance is proportional to the induction area of the plate capacitor. The pen head of the stylus pen and the touchscreen need to form a surface touch. Conventional stylus pens have the following shortcomings.
1. The pen head has a flat end face, namely, the front end of the pen head has a soft flat face which is perpendicular to the pen rod. When in use, the pen rod subject to the flat end face must be at right angle relative to the touchscreen for the pen head to touch the touchscreen. It is inconvenient for the user who is not familiar with the stylus pen.
2. The pen head has an inclined guide face. The pen head has an angle relative to the pen rod. This is helpful to use the stylus pen at a certain angle only. When the direction is changed, it is laborious to move the pen head on the screen.
3. The pen head has an inclined guide face. This pen head is flexible to move on the screen. If the applied force is too less, the contact area of the pen head to touch the screen is too small to satisfy the stylus function. If the applied force is too great, the contact area of the pen head to touch the screen is larger, but it is difficult to move the pen head.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems.